The present invention comprises a novel intrauterine contraceptive device (IUD) as well as methods for the detection and removal of an IUD from a female patient.
IUDs of various shapes are often provided with a "tail" of a monofilament plastic which extends through the cervix and allows one to remove the IUD when desired by pulling the tail. However, the presence of a tail is associated with pelvic inflammatory disease (PID) as reported by H. J. Tatum in Fertility and Sterility, Volume 39, No. 2, pps. 141-143 (1983), by N. C. Lee et al. in Obstetrics & Gynecology, No. 1, Vol. 62, July 1983 and by R. H. Kaufman et al. in Obstetrics & Gynecology, Supplement, page S88, September 1983.
In more detail, the tail of an IUD which extends from the endometrial cavity down through the cervical canal and into the vagina has been suspected since 1920 of providing a "ladder" for bacteria to ascend from the vagina into the internal pelvic and reproductive organs (uterus, fallopian tubes, ovaries, and adjacent structures). Clinical studies have suggested that the uterine cavity sterilizes itself within 30 days after an IUD has been inserted, see D. R. Mishell et al. in Obstetrics & Gynecology, page 119, Sept. 1, 1966. If the IUD has a mono-or difilamented transcervical tail which extends into the vagina, small numbers of bacteria may persist in the uterine cavity for more than 30 days. A parallel study using an IUD whose tail had been removed suggested that the uterus remained sterile for an indefinite period of time following the insertion. Although IUDs bearing multifilamented tails (Dalkon Shield, Majzlin Springs, and Birnberg Bows) are particularly liable to result in an ascending pelvic infection, the mono-or difilamented tailed IUDs (Lippes loop, Sof-T-Coil, Tatum T, GYNE-T.TM., Copper T, and Copper 7) may not be totally free from risk. The long term use of a tailed IUD may contribute to an infection which ascends from the vagina and into the reproductive pelvic organs. Such an infection may result in reduced fertility.
PID may result from direct spread of micro-organisms from the vagina up through the uterine cavity (endometritis) and fallopian tubal cavities (salpingitis) and then may extend to the ovaries (oophoritis). Where both tubes and ovaries are involved, a very severe form of PID - the tubo-ovarian abscess may occur. The tubo-ovarian abscess is a potentially life threatening complication. PID may also spread upward from the uterus (cervix and fundus) via the pericervical and perimetrial lymphatics to the periovarian and mesosalpinx areas and including the urinary bladder, bowel, kidneys and omentum. Much less frequently, the periurethral and parivesical lymphatics may carry micro-organisms to the bladder and upper urinary tract. It is therefore not illogical to assume that the transcervical tail of an IUD might contribute to these types of pelvic inflammatory diseases. A tailless IUD would minimize or negate the role of the IUD as a contributing factor to the development of PID.
Transuterine perforation of a tailed IUD into the peritoneal cavity may provide a conduit for bacteria to move from the vagina through the uterine cavity and into the peritoneal cavity. When the tail which had been in contact with the bacterial flora in the vagina enters the peritoneal cavity following the perforation of the uterus peritonitis may occur.
Further, a transcervical IUD tail may cause an irritation of the cervical epithelium resulting in acute and/or chronic cervicitis. This in turn may be accompanied by a vaginal discharge. An intrauterine pregnancy which occurs while an IUD is in the uterine cavity has been shown to increase the risk of an abortion or premature labor. By the 10th to 12th week of pregnancy and when the IUD has a tail, the tail is often retracted up into the uterine cavity. Bacteria which are near, on to or within that portion of the tail which had originally been in the vagina may cause a midtrimester septic abortion when they enter the cavity of the pregnant uterus. Such midtrimester septic abortion is a potentially life threatening complication both for the mother and for the fetus. It is logical that a pregnancy which occurs while a tailless IUD is in the uterus should not be threatened by an ascending infection since there would not have been a transcervical tail in the vagina to serve as a conduit for bacteria to ascend upward into the uterus.
Detection of an IUD in the uterus and its removal important aspects of the design of the IUD. IUDs are placed in the uterus for extended periods of time during which inadvertent removal or expulsion may occur, e.g., when removing a tampon or during a menstrual period. While the presence of the tail provides such a means of detection and removal, the presence of the tail may be irritating to the wearer.
The use of magnetic materials in IUDs is known as seen by reading of RCA Technical Notes No. 675 (June 1966) and U.S. Pat. Nos. 3,042,030; 3,467,087; 3,805,777; 3,908,646; 3,913,573; and 3,996,933. Such magnetic IUDs are provided to allow for external detection, e.g., by passing a compass needle across the abdomen, or for removal of the IUD. However, the removal systems described in the references depend upon the attractive force between the magnet of the IUD and the magnetic probe inserted into the uterus to be sufficient to allow removal of the magnetic probe from the uterus with the magnet attached to it i.e., by magnetic attractive forces. Such designs are unrealistic and impractical in that the magnetic force required to carry out such a manipulation through the cervix is far greater than that which may be obtained with magnets sufficiently small to be used in an IUD. This limitation may have been recognized in U.S. Pat. No. 3,805,777, wherein the magnet is provided in a tab which is, in effect, a tail carried within the IUD. A magnetic probe is inserted into the uterus and pulls the tab through the cervix whereupon it is grasped and the entire IUD is then removed by pulling on the tab. It is believed that the maximum magnetic force which could be used in such a system would still be insufficient to allow the tab to be manipulated through the cervix during many, if not most or all, attempts at such an operation. In addition, the magnetic tab of such a system can become a tail by inadvertently falling through the cervix.
It is an object of the present invention to provide an IUD which is readily and accurately detected in the uterus by non-invasive external means or by means of a probe inserted intravaginally or intrarectally without invasion of the uterus.
A further object of the present invention is an IUD which is tailess and yet which is readily removed from the uterus with a minimum amount of intrauterine manipulation.
A further object of the present invention is a system for removing an IUD containing a magnetic portion with minimal manipulation in the body. By accurately and quickly locating the IUD, such a system reduces the risk of infection, perforating the uterus or other trauma and reduces to a minimum the discomfort of the patient.
A further object of the present invention is an extraction system which is applicable to a wide variety of IUD shapes and sizes so as to avoid the necessity for separate and unique extractors for individual shapes of IUDs.